Hive Mind (Ex): Gladiator lizards hatch in broods of two to four individuals. Brood-mates within 50 miles of each other are in constant telepathic communication. If one brood-mate is aware of a particular danger, they all are. If one in a group is not flat-footed, none of them are. No gladiator lizard in a group of brood-mates is considered flanked unless all of them are.
You know, all the AD&D versions specify the link is only between two individuals, not an entire brood.
I think I prefer the paired version I proposed.
Hive Mind (Ex): Gladiator lizards hatch in pairs, called brood-mates. Brood-mates within 50 miles of each other are in constant telepathic communication. If one brood-mate is aware of a particular danger, both are. If one in a pair is not flat-footed, neither of them is. No gladiator lizard in a pair of brood-mates is considered flanked unless both of them are.
Hmm, tempted to rename it to differentiate the ability from standard Hive Mind:
Brood-Mate (Ex): Gladiator lizards hatch in pairs, called brood-mates. Brood-mates within 50 miles of each other are in constant telepathic communication. If one brood-mate is aware of a particular danger, both are. If one in a pair is not flat-footed, neither of them is. No gladiator lizard in a pair of brood-mates is considered flanked unless both of them are.
Also, the 2E version gives them an advantage when teaming up against an opponent: "If both lizards strike the same target in the same round, the second lizard to strike gains +1 to hit on both its blows."
That suggests some kind of Special Attack if two Lizards engage the same opponent.
Maybe:
Brood-Mate #2 (Ex): Gladiator lizards hatch in pairs, called brood-mates. Brood-mates within 50 miles of each other are in constant telepathic communication. If one brood-mate is aware of a particular danger, both are. If one in a pair is not flat-footed, neither of them is. No gladiator lizard in a pair of brood-mates is considered flanked unless both of them are.
If both brood-mates attack the same opponent in a round, each gains a +1 circumstance bonus to their attack roll.